Windows 8 Pro Preorder for $69.99 plus $30 Amazon Credit
Amazon is offering $30 credits for their website when you pre-order a physical copy of Windows 8 Pro for $69.99. This is a great deal if you buy on Amazon often like I do (especially if you use Amazon Prime). The gift code will be emailed 30 days after the the order ships (October 25th if you pre-order) and cannot be used on Amazon digital purchases.
If you are looking to purchase an upgrade to Windows 8 Pro, this is the way to go.